Laser printers are employed as computer printers and provide high speed, high quality printing of text and graphics. These printers include complex and sophisticated electro-optical, electro-mechanical and electronic assemblies which must be maintained in precise working order in order for the printer to perform appropriately. The printer is usually employed within an office or other setting and is used by personnel who are not usually capable of technical maintenance of the apparatus. Service personnel who attend to maintenance of the apparatus would have to possess a relatively high level of skill to diagnose and maintain the printer if such diagnosis and maintenance activities were to be performed on a manual basis. The complexity of the apparatus and the level of skill required for proper diagnosis and maintenance is sufficiently high as to make maintenance on a manual basis unrealistic for such apparatus which is expected to function as a piece of office equipment, and which is expected to be functional on a day to day basis. Automatic test systems are known for office equipment such as copiers and computers, however these systems usually provide only a limited number of tests to denote overall operability and do not provide the means for exercising each critical assembly for possible defect. Known autotest systems also usually function in accordance with a fixed routine which cannot be altered or varied by the service personnel, and which often does not provide a sufficient or variable number of tests which would be useful to appropriately monitor the operability of the equipment.